2012-2013 Microchip Technology Inc. DS50002063B
MCP16301
High-Performance Low-Noise
5V Output Buck Converter
Evaluation Board
User’s Guide
DS50002063B-page 2 2012-2013 Microchip Technology Inc.
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ISBN: 978-1-62077-420-5
2012-2013 Microchip Technology Inc. DS50002063B-page 3
Object of Declaration: MCP16301 High-Performance Low-Noise 5V Output
Buck Converter Evaluation Board User’s Guide
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
2012-2013 Microchip Technology Inc. DS50002063B-page 4
Table of Contents
Preface ...........................................................................................................................5
Introduction............................................................................................................ 5
Document Layout .................................................................................................. 5
Conventions Used in this Guide............................................................................ 6
Recommended Reading........................................................................................7
The Microchip Web Site........................................................................................ 7
Customer Support.................................................................................................7
Document Revision History................................................................................... 7
Chapter 1. Product Overview
1.1 Introduction ..................................................................................................... 9
1.2 MCP16301 Short Overview ............................................................................9
1.3 What Is the MCP16301 High Performance Low Noise 5V Buck Converter
Evaluation Board? ..................................................................................11
1.4 MCP16301 High Performance Low Noise 5V Buck Converter
Evaluation Board Kit Contents ................................................................ 11
Chapter 2. Installation and Operation
2.1 Introduction ...................................................................................................13
2.2 Getting Started ............................................................................................. 14
Appendix A. Schematic and Layouts
A.1 Introduction ..................................................................................................21
A.2 Board – Schematic ....................................................................................... 22
A.3 Board – Top Silk And Copper ......................................................................23
A.4 Board – Mid Inner Layer 1 ...........................................................................24
A.5 Board – Mid Inner Layer 2 ...........................................................................25
A.6 Board – Bottom Copper and Pads ...............................................................26
Appendix B. Bill of Materials (BOM).......................................................................... 27
Worldwide Sales and Service ....................................................................................28
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
2012-2013 Microchip Technology Inc. DS50002063B-page 5
Preface
INTRODUCTION
This chapter contains general information that will be useful to know before using the
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board. Items
discussed in this chapter include:
• Document Layout
• Conventions Used in this Guide
• Recommended Reading
• The Microchip Web Site
• Customer Support
• Document Revision History
DOCUMENT LAYOUT
This document describes how to use the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board as a development tool to emulate and debug firm-
ware on a target board. The manual layout is as follows:
•Chapter 1. “Product Overview” – Important information about the MCP16301
High-Performance Low-Noise 5V Buck Converter Evaluation Board
•Chapter 2. “Installation and Operation” – Includes instructions on how to get
started with the MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board and a description of the user’s guide
•Appendix A. “Schematic and Layouts” – Shows the schematic and layout
diagrams for the MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board
•Appendix B. “Bill of Materials (BOM)” – Lists the parts used to build the
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
NOTICE TO CUSTOMERS
All documentation becomes dated, and this manual is no exception. Microchip tools and
documentation are constantly evolving to meet customer needs, so some actual dialogs
and/or tool descriptions may differ from those in this document. Please refer to our web site
(www.microchip.com) to obtain the latest documentation available.
Documents are identified with a “DS” number. This number is located on the bottom of each
page, in front of the page number. The numbering convention for the DS number is
“DSXXXXXA”, where “XXXXX” is the document number and “A” is the revision level of the
document.
For the most up-to-date information on development tools, see the MPLAB® IDE online help.
Select the Help menu, and then Topics to open a list of available online help files.
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 6 2012-2013 Microchip Technology Inc.
CONVENTIONS USED IN THIS GUIDE
This manual uses the following documentation conventions:
DOCUMENTATION CONVENTIONS
Description Represents Examples
Arial font:
Italic characters Referenced books MPLAB® IDE User’s Guide
Emphasized text ...is the only compiler...
Initial caps A window the Output window
A dialog the Settings dialog
A menu selection select Enable Programmer
Quotes A field name in a window or
dialog “Save project before build”
Underlined, italic text with
right angle bracket A menu path File>Save
Bold characters A dialog button Click OK
A tab Click the Power tab
N‘Rnnnn A number in verilog format,
where N is the total number of
digits, R is the radix and n is a
digit.
4‘b0010, 2‘hF1
Text in angle brackets < > A key on the keyboard Press <Enter>, <F1>
Courier New font:
Plain Courier New Sample source code #define START
Filenames autoexec.bat
File paths c:\mcc18\h
Keywords _asm, _endasm, static
Command-line options -Opa+, -Opa-
Bit values 0, 1
Constants 0xFF, ‘A’
Italic Courier New A variable argument file.o, where file can be
any valid filename
Square brackets [ ] Optional arguments mcc18 [options] file
[options]
Curly brackets and pipe
character: { | } Choice of mutually exclusive
arguments; an OR selection errorlevel {0|1}
Ellipses... Replaces repeated text var_name [,
var_name...]
Represents code supplied by
user void main (void)
{ ...
}
Preface
2012-2013 Microchip Technology Inc. DS50002063B-page 7
RECOMMENDED READING
This user's guide describes how to use the MCP16301 High-Performance Low-Noise
5V Buck Converter Evaluation Board. Other useful documents are listed below. The
following Microchip documents are available and recommended as supplemental
reference resources.
• MCP16301 Data Sheet – “High-Voltage Input Integrated Switch Step-Down
Regulator” (DS25004)
• MCP16301 High-Voltage Buck-Boost Demo Board User’s Guide (DS52020)
• MCP16301 High-Voltage Buck Converter 600 mA Demo Board User’s Guide
(DS51978)
THE MICROCHIP WEB SITE
Microchip provides online support via our web site at www.microchip.com. This web
site is used as a means to make files and information easily available to customers.
Accessible by using your favorite Internet browser, the web site contains the following
information:
•Product Support – Data sheets and errata, application notes and sample
programs, design resources, user’s guides and hardware support documents,
latest software releases and archived software
•General Technical Support – Frequently Asked Questions (FAQs), technical
support requests, online discussion groups, Microchip consultant program
member listing
•Business of Microchip – Product selector and ordering guides, latest Microchip
press releases, listing of seminars and events, listings of Microchip sales offices,
distributors and factory representatives
CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
• Distributor or Representative
• Local Sales Office
• Field Application Engineer (FAE)
• Technical Support
Customers should contact their distributor, representative or field application engineer
(FAE) for support. Local sales offices are also available to help customers. A listing of
sales offices and locations is included in the back of this document.
Technical support is available through the web site at:
http://www.microchip.com/support.
DOCUMENT REVISION HISTORY
Revision B (August 2013)
• Updated the board layout in Figure 2-2.
• Updated the A.3 “Board – Top Silk And Copper” and A.6 “Board – Bottom
Copper and Pads” layouts in Appendix A. “Schematic and Layouts”.
• Updated Appendix B. “Bill of Materials (BOM)”.
Revision A (June 2012)
• Initial Release of this Document.
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 8 2012-2013 Microchip Technology Inc.
NOTES:
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
2012-2013 Microchip Technology Inc. DS50002063B-page 9
Chapter 1. Product Overview
1.1 INTRODUCTION
This chapter provides an overview of the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board and covers the following topics:
• MCP16301 Short Overview
• What Is the MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board?
• MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
Kit Contents
1.2 MCP16301 SHORT OVERVIEW
The MCP16301 device is a highly integrated, high-efficiency, fixed frequency,
step-down DC-DC converter in a popular 6-pin SOT-23 package, that operates from
input voltage sources up to 30V. Integrated features include a high-side switch, fixed
frequency peak current mode control, internal compensation, peak current limit and
overtemperature protection.
All control system components necessary for stable operation over the entire device
operating range are integrated.
High-converter efficiency is achieved by integrating the current-limited, low-resistance,
high-speed N-Channel MOSFET and associated drive circuitry. High-switching fre-
quency minimizes the size of the external filtering components, resulting in a small
solution size.
The MCP16301 is a high-input voltage step-down regulator, capable of supplying a
maximum of 600 mA to a regulated output voltage from 2.0V to 15V. An integrated pre-
cise 0.8V reference combined with an external resistor divider sets the desired con-
verter output voltage. The internal reference voltage rate of rise is controlled during
startup, minimizing the output voltage overshoot and the inrush current.
The internally trimmed 500 kHz oscillator provides a fixed frequency, while the peak
current mode control architecture varies the duty cycle for output voltage regulation. An
internal floating driver is used to turn the high side integrated N-Channel MOSFET on
and off. The power for this driver is derived from an external boost capacitor whose
energy is supplied from a fixed voltage ranging between 3.0V and 5.5V, typically the
output voltage of the converter. For applications with 5.5V < VOUT < 15V and
VIN < 30V, an alternative boost supply must be used (from input derived, output derived
or an auxiliary system voltage). For more information and examples, see the
MCP16301 data sheet.
The EN input is used to enable and disable the device. If disabled, the MCP16301
device consumes 7 µA (typical) from the input. An integrated Under Voltage Lockout
(UVLO) prevents the converter from starting until the input voltage is high enough for
normal operation. The converter will typically start at 3.5V and operate down to 3.0V.
An overtemperature protection limits the silicon die temperature to +150°C by turning
the converter off. The normal switching resumes at +120°C.
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 10 2012-2013 Microchip Technology Inc.
FIGURE 1-1: Typical MCP16301 3.3V OUT Application.
1.2.1 MCP16301 Features
• Up to 96% Typical Efficiency
• Input Voltage Range: 4.0V to 30V
• Output Voltage Range: 2.0V to 15V
• 2% Output Voltage Accuracy
• 600 mA Output Current
• Quiescent Current (Switching Mode, No Load): 2 mA Typical
• Quiescent Current (Shutdown, EN = 0): 7 µA Typical
• 500 kHz Fixed Frequency
• Peak Current Mode Control
• Internal Compensation
• Internal Soft-Start
• Cycle-by-Cycle Peak Current Limit
• Undervoltage Lockout (UVLO): 3.5V to Start, 3.0V to Stop
• Overtemperature Protection
• Package type: SOT-23-6
VIN
GND
V
FB
SW
VIN
4.5V To 30V
VOUT
3.3V @ 600 mA
COUT
22 µF
CIN
22 µF
L1
15 µH
BOOST
31.2 K
10 K
EN
1N4448
40V
Schottky
Diode
CBOOST
100 nF
Product Overview
2012-2013 Microchip Technology Inc. DS50002063B-page 11
1.3 WHAT IS THE MCP16301 HIGH-PERFORMANCE LOW-NOISE 5V BUCK
CONVERTER EVALUATION BOARD?
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board is
designed to operate from a 6V to 30V input and regulate the output to 5V, while deliv-
ering a maximum 600 mA of load current.
The evaluation board is optimized for a high-efficiency and low-output noise and ripple,
especially at 12V Input and 100 mA load current. Because the MCP16301 is switching
fast to achieve high efficiency, high-frequency noise is generated and may affect some
RF systems. This evaluation board demonstrates a low-noise, high-performance
design.
FIGURE 1-2: MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board Block Diagram.
1.4 MCP16301 HIGH-PERFORMANCE LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD KIT CONTENTS
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board kit
includes:
• MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
• Important Information Sheet
VIN = 12V Input
VIN
EN
SW L
RBOOST
RT
VOUT = 5V
FB
CIN
COUT
RB
BOOST
CBOOST
RSnubber
CSnubber
BOOST Diode
GND
120 pF
4R7 52k3
10k
82R 100 nF
22 µF
22 µH
MCP16301
22 µF
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 12 2012-2013 Microchip Technology Inc.
NOTES:
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
2012-2013 Microchip Technology Inc. DS50002063B-page 13
Chapter 2. Installation and Operation
2.1 INTRODUCTION
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board is
used to demonstrate a high-voltage input DC-DC converter design, that can deliver
high efficiency, while minimizing high-frequency switching noise. The board steps down
high-input voltages, up to 30V, to a low-output voltage, having more than 90% efficiency
and a minimum of 30 mV output ripple.
High-frequency input/output noise generated by the switching converters can reach
high-noise levels that interfere with other devices powered from the same source. The
high amplitude of high-frequency noise can disturb some RF systems.
High efficiency is achieved with the MCP16301 buck converter by switching the inte-
grated N-Channel MOSFET at a high speed. This high speed can cause disturbances
to other system components if the high-speed switching edges of the converter are not
minimized. The designer must be concerned with:
• good PCB layout practice
• choosing high-quality shielded inductors and low Equivalent Series Resistance
(ESR) capacitors
• choosing an RC snubber or a RBOOST resistor to properly limit the speed of the
internal N-Channel MOSFET switch (see Figure 1-2).
The evaluation board is optimized for 12V Input and 100 mA load.
2.1.1 MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board Features
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
has the following key features:
• Input Voltage: 6 to 30V
• Output Voltage: 5V
• Output Capability: 600 mA Load Current
• Output Ripple Plus Noise: 30 mVp-p @ 12V Input and 100 mA Load
• Low-Radiated Noise
• Efficiency: Up to 91% @ 12V Input (see Figure 2-1)
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 14 2012-2013 Microchip Technology Inc.
FIGURE 2-1: Efficiency vs. Load Current at 12V Input.
2.2 GETTING STARTED
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board is
fully assembled and tested to evaluate and demonstrate the MCP16301 design.
2.2.1 Power Input and Output Connection
2.2.1.1 POWERING THE MCP16301 HIGH-PERFORMANCE LOW-NOISE 5V
BUCK CONVERTER EVALUATION BOARD
When the board is ready for evaluation, apply positive input voltage to the VIN terminal
and the corresponding return to the ground terminal. The maximum input voltage
should not exceed 30V. An electronic load or resistive load can be used for evaluation.
The electronic loads attempt to sink current at 0V during startup. A resistive load or con-
stant resistance is recommended for startup evaluation. Connect the positive voltage
terminal of the load to the VOUT terminal on the evaluation board, and connect the neg-
ative or return side of the load to the ground terminal.
Connectors are placed on the bottom side of board:
•V
IN for positive power
• Two grounds for negative power
•V
OUT connector for output load
40
50
60
70
80
90
0 100 200 300 400 500
600
Efficiency (%)
I
OUT
(mA)
Installation and Operation
2012-2013 Microchip Technology Inc. DS50002063B-page 15
2.2.2 Board Testing
To test the board, follow these steps:
1. Apply the input voltage.
2. An external pull up resistor is connected from VIN to the EN input of the
MCP16301. Once the input voltage is greater than 3.5V, the device begins to
switch. Apply greater than 6V supply to the input for proper operation. A minimum
load is required to regulate the output to 5V. For minimum load requirements
(light load conditions), see the device data sheet for detailed information.
3. The measured output voltage should be 5V typical. Adjusting the input voltage
and load should not cause the output to vary more than a few mV over the oper-
ating range of the converter.
4. Typical conditions for evaluating the board are: 12V input, 100 mA load. Using
an oscilloscope, measure the AC ripple of the output without any bandwidth lim-
itation. VOUT ripple plus noise should be approximately 30 mV. To avoid errors,
remove the ground lead of the scope probe and measure the output ripple on the
output capacitors pads. Use a short wire wrapped around the ground barrel of
the probe to touch the capacitor’s ground pad.
Additional analysis can be performed by changing the RC snubber and RBOOST resistor
values (see Figure 2-1). These additional circuits lower the efficiency, but reduce
switching noise.
FIGURE 2-2: MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board Setup
Circuit.
Note: The VOUT ripple plus noise value varies with the input and output
parameters.
Set 12V
Power Supply V-Meter R
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 16 2012-2013 Microchip Technology Inc.
2.2.3 How Does the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board Work?
The MCP16301 integrates a low resistance N-Channel MOSFET (typically 460 m). A
high-side or floating supply is needed to drive the gate of the N-Channel MOSFET
above the input voltage (to turn it on). The evaluation board uses the 5V output voltage
to charge the boost capacitor (CBOOST), while the inductor current flows, clamping the
SW node to a diode drop below ground. Prior to start up, there is no inductor current,
so an internal precharge circuit charges the boost cap up to a minimum threshold.
Once CBOOST is charged, the N-Channel MOSFET can be turned on, ramping current
into the inductor. The BOOST diode is used to provide a charging path for the CBOOST
capacitor, while current is flowing through the inductor.
The two sense resistors (RT and RB in Figure 2-1) set the output (VOUT) at 5.0V accord-
ing to the following equation:
EQUATION 2-1:
where VFB = 0.8V is the reference voltage of the FB pin. The transconductance error
amplifier gain is controlled by its internal impedance. The external divider resistors
have no effect on system gain, so a wide range of values can be used. A 10 k resistor
is recommended as a good trade-off for quiescent current and noise immunity.
The MCP16301 device features integrated slope compensation to prevent the bimodal
operation of the pulse-width modulation (PWM) duty cycle. Internally, approximately
half of the inductor current down slope is summed with the internal current sense
signal. For the proper amount of slope compensation, it is recommended to keep the
inductor down-slope current constant by varying the inductance with VOUT. For 5.0V
output, a 22 µH inductor is recommended.
The input capacitor must filter the high input ripple current, as a result of pulsing or
chopping the input voltage. The MCP16301 input voltage pin is used to supply voltage
for the power train and as a source for internal bias. A low Equivalent Series Resistance
(ESR), preferably a ceramic capacitor, is recommended. The necessary capacitance is
dependent upon the maximum load current and source impedance. Minimum
capacitance at light load is 2.2 µF.
The output capacitor helps in providing a stable output voltage during sudden load
transients, and reduces the output voltage ripple. The minimum value of the output
capacitance is limited to 20 µF, due to the integrated compensation of the MCP16301.
The freewheeling diode creates a path for inductor current flow after the internal switch
is turned off. The efficiency of the converter is a function of the forward drop voltage
value and speed of the freewheeling Schottky diode.
For detailed information, see the MCP16301 Data Sheet (DS25004).
RTOP RBOT VOUT
VFB
-------------1–
=
Installation and Operation
2012-2013 Microchip Technology Inc. DS50002063B-page 17
2.2.4 Reduction of the High Frequency Switching Noise
Because the MCP16301’s internal MOSFET is switching at 500 kHz, high-frequency
noise may appear. This can affect the circuitry in close proximity. Parasitic elements
generate ringing. There are two main noise sources. The first source occurs at the
fundamental switching frequency and is called “Output Ripple”. The second source,
associated with high-frequency ringing, occurs during the ON-OFF transition of the
integrated N-Channel MOSFET switch. This results in a high-frequency noise that can
be in the range of 100s of MHz and up to 500 mV peak-to-peak voltage ripple. Both
noise components require separate filtering. Figure 2-3 shows an example of the two
noise components.
FIGURE 2-3: VOUT Ripple and Noise for an MCP16301 Buck Converter
Without Any Noise Reduction Components.
The low-frequency output ripple of the MCP16301 is generally less than 20 mV
peak-to-peak, and it depends on the output capacitor value and capacitor dielectric
type. Low ESR and Equivalent Series Inductance (ESL) ceramic capacitors signifi-
cantly decrease the output voltage low-frequency ripple.
Additional output capacitance does not remove the high-frequency noise. Ceramic
capacitors have high-impedance in the frequency band in which this noise occurs. The
ringing frequency is very high, and the output capacitor alone or an extra low-value
capacitor in parallel with it are ineffective in attenuating this noise. First, the noise can
be attenuated by good PCB design practices. A four-layer board is recommended in
this case. The solution is to place the SW node of the MCP16301 pin into the inner layer
(Mid-Layer 2) as an individual plane between two ground planes (Mid-Layer 1 and
Layer 4 - Bottom plane).
High-quality shielded inductors reduce the spreading of electromagnetic fields, a
desirable characteristic of any power supply. An example of a high-quality shielded
inductor is the CoilCraft Inc. XAL6060.
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 18 2012-2013 Microchip Technology Inc.
The third and most effective method to reduce switching noise is to slow down the
turn-on of the integrated N-Channel MOSFET switch, addressing the noise at its
source. This method lowers the efficiency of the converter insignificantly
(see Figure 2-6), but the noise in the system is significantly reduced. A RBOOST
resistance value between 47 and 100 Ohms was typical for this analysis.
Placing an RC snubber in parallel with the external Schottky diode is another method
that can be used to reduce high-frequency noise. Some basic equations are used to
calculate the RC snubber values.
For example, the Schottky rectifier diode MBRA140T (1A/40V) has a parasitic
Lp= 2 nH and Cp= 38 pF (see the MBRA140T data sheet for details). When measuring
the MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board cir-
cuit without an RC snubber (for 12V Input and 100 mA load), the ringing frequency is
approximately 250 MHz. Considering the parasitic inductance equal to LP, calculate the
parasitic impedance, using the following equation:
EQUATION 2-2:
For this example, Z is approximately 3. Choose a snubber resistor to be similar or
greater than this value (4.7 standard value).
EQUATION 2-3:
With the value of RSnubber established, the snubber’s capacitor value results from the
following equation:
EQUATION 2-4:
Z2
fLp
=
RSnubber Z
Where:
RSnubber =4.7
CSnubber 1
2
fRSnubber
-----------------------------=
Where:
CSnubber = 120 pF
Installation and Operation
2012-2013 Microchip Technology Inc. DS50002063B-page 19
Figures 2-4 –2-6 show the results for the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board:
• AC output ripple for board with RC snubber only (Figure 2-4)
• AC output ripple for RC snubber and RBOOST on board (Figure 2-5)
• Efficiency comparison with RC snubber and RBOOST (Figure 2-6)
FIGURE 2-4: VOUT Ripple of the Evaluation Board is less than 80 mVp-p using
RC Snubber only (12V Input, 100 mA Load). Compare to Figure 2-3.
FIGURE 2-5: VOUT Ripple of the Evaluation Board is less than 30 mVp-p using
RC Snubber and RBOOST (12V Input, 100 mA Load). Compare to Figures 2-3 and 2-4.
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 20 2012-2013 Microchip Technology Inc.
FIGURE 2-6: Efficiency Comparison for the MCP16301 High-Performance
Low-Noise 5V Buck Converter Evaluation Board (12V and 24V Input).
40
50
60
70
80
90
0 100 200 300 400 500
600
Efficiency (%)
I
OUT
(mA)
Vin = 12V, no RC Snubber, no RBoost
Vin = 24V no RC Snubber, no RBoost
Vin = 12V, RC Snubber, no RBoost
Vin = 24V, RC Snubber, no RBoost
Vin = 12V, Snubber, RBoost
Vin = 24V, Snubber, RBoost
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